Flickity WordPress Carousel

flickity-carousel.php

<?php
/**
 * Flickity-based carousel for returning posts from the loop. I find it far more versatile and simple than a Bootstrap
 * carousel. Get the required scripts and styles from here: https://flickity.metafizzy.co/
 */

<div class="blog-carousel">
	<?php
		if ( have_posts() ) : while ( have_posts() ) : the_post();

		$thumbnail_id = get_post_thumbnail_id();
		$thumbnail_url = wp_get_attachment_image_src( $thumbnail_id, 'large', true );
	?>
	<div class="carousel-cell">
		<!-- I chose to display my posts in a custom card style. -->
		<article class="article-card"> 
			<a href="<?php the_permalink(); ?>"><img src="<?php echo $thumbnail_url[0]; ?>" alt="<?php the_title(); ?>" class="card-img"></a>
			<div class="card-content">
				<a href="<?php the_permalink(); ?>" class="article-title"><?php the_title( "<h4>", "</h4>" ) ?></a>
			</div>
			<footer class="card-footer">
				<a href="<?php the_permalink(); ?>" class="button purple-outline" role="button">Learn More</a>
			</footer>
		</article>
	</div>
	<?php 
		endwhile;
		endif; 
		wp_reset_query(); 
	?>
</div>
?>